(a) Field of the Invention
The present invention relates to an organic electroluminescent display device, more particularly, to an organic electroluminescent display device comprising an ultraviolet (UV) light stabilizer as a constituent.
(b) Description of Related Art
A conventional organic electroluminescent display device consists of various layers such as anode and cathode electrodes, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer and an electron injection layer. In the case of a small molecular organic electroluminescent display device, the respective layers can be introduced by vacuum deposition, and it is easy to mix at least one or more materials in one layer through use of the co-deposition method.
In the case where a polymer layer is used as a hole injection layer, a UV stabilizer can be dissolved along with the solution during preparation of the solution so that a soluble UV stabilizer is used and only the desired part of the polymer layer is formed by a wet process.
A structural approach for making a barrier in a polymer-ceramic-polymer shape to prevent deterioration of the characteristics as the environment affects the components of an organic electroluminescent display device is introduced in U.S. Pat. Nos. 6,497,598 and 6,268,695. However, these prior patents do not teach a detailed device structure using additives capable of directly reducing the environmental effects upon electroluminescent (EL) components.